The geography of New Caledonia[1] (Nouvelle-Calédonie), an overseas collectivity of France located in the subregion of Melanesia, makes the continental island group unique in the southwest Pacific.

The New Caledonian archipelago is a microcontinental island chain which originated as a fragment of Zealandia, a nearly submerged continent or microcontinent which was part of the southern supercontinent of Gondwana during the time of the dinosaurs.

The Grande Terre group of New Caledonia, with Mont Panié at 1,628 meters (5,341 feet) as its highest point, is the most elevated part of the Norfolk Ridge, a long and mostly underwater arm of the continent.

Bernard Pelletier argues that Grande Terre was completely submerged for millions of years, and hence the origin of the flora may not be local in nature, but due to long distance-dispersal.

[11] Given its continental origin as a fragment of Zealandia, unlike many of the islands of the Pacific such as the Hawaiian chain, New Caledonia is not of geographically recent volcanic provenance.

Since the age of the dinosaurs, as the island moved north due to the effects of continental drift, some geologists assert that it may have been fully submerged at various intervals.

Botanists, however, argue that there must have been some areas that remained above sea level, serving as refugia for the descendants of the original flora that inhabited the island when it broke away from Gondwana.

While rainfall in the neighboring Vanuatu islands averages two meters annually, from the north of New Caledonia to the south the rain decreases to a little over 1,000 mm (39 in).

The capital, Nouméa, located on a peninsula on the southwestern coast of the island normally has a dry season which increases in intensity from August until mid-December, ending suddenly with the coming of rain in January.

[23] It has a catchment area of 620 square kilometres and opens north-westward into the Baie d'Harcourt, flowing towards the northern point of the island along the western escarpment of the Mount Panie.

Given its geographical isolation since the end of the Cretaceous, New Caledonia is a refugium, in effect a biological "Noah's Ark", an island home to both unique living plants and animals and also to its own special fossil endowment.

[29] Given their prehistoric appearance, the dry forests of western New Caledonia were chosen as the location for filming the first episode of the BBC miniseries Walking with Dinosaurs, which was set in the Arizona of the late Triassic.

After a formation discovered in Oman in the 1970s, New Caledonia has the planet's largest known outcrop of ultrabasic rock, derived not from the crust, but from an upthrust fold of the more deeply underlying mantle of the earth.

The toxicity of the mineral-rich soil has helped preserve the endemic vegetation, which has long been adapted to it, from competition from would-be colonizers which find it unsuitable.

[31] Anthropologically, New Caledonia is considered the southernmost archipelago of Melanesia, grouping it with the more close by islands to its north, rather than its geologically associated neighbour, New Zealand, to the south.

[32] The Lapita culture, hypothesized to have spoken proto-Oceanic, and defined by its typical style of pottery, originated to the northwest in the Bismarck Archipelago around 1500 BC.

The rest of the population is made up of ethnic groups that arrived in New Caledonia in the last 150 years: Europeans (34.5%) (predominantly French, with German, British and Italian minorities), Polynesians (Wallisians, Tahitians) (11.8%), Indonesians (2.6%), Vietnamese (1.4%), Ni-Vanuatu (1.2%), and various other groups (3.9%), Tamils, other South Asians, Berbers, Japanese, Chinese, Fijians, Arabs, West Indian (mostly from other French territories) and a small number of ethnic Africans.